Raman spectroscopic analysis of the clonal and horizontal spread of CTX-M-15-producing Klebsiella pneumoniae in a neonatal intensive care unit.

Nosocomial outbreaks of extended-spectrum ß-lactamase (ESBL)-producing Klebsiella pneumoniae are an increasing concern in neonatal intensive care units (NICUs). We describe an outbreak of ESBL-producing K. pneumoniae that lasted 5 months and affected 23 neonates in our NICU. Proton pump inhibitor and extended-spectrum cephalosporin exposure were significantly associated with the risk of ESBL-producing K. pneumoniae colonisation and/or infection. Thirty isolates recovered from clinical, screening and environmental samples in the NICU were studied by means of Raman spectroscopy, pulsed-field gel electrophoresis and repetitive extragenic palindromic polymerase chain reaction (rep-PCR). The Raman clustering was in good agreement with the results of the other two molecular methods. Fourteen isolates belonged to the Raman clone 1 and 16 to the Raman clone 3. Molecular analysis showed that all the strains expressed SHV-1 chromosomal resistance, plasmid-encoded TEM-1 and CTX-M-15 ß-lactamases. Incompatibility groups of plasmid content identified by PCR-based replicon typing indicated that resistance dissemination was due to the clonal spread of K. pneumoniae and horizontal CTX-M-15 gene transfer between the two clones.

[Unusual location of a brain abscess due to Listeria monocytogenes]. / Abcès cérébral à Listeria monocytogenes de localisation inhabituelle.

Here we report a case of sustentorial brain abscess due to Listeria monocytogenes. Blood culture and procalcitonine blood measurement were negative. L. monocytogenes was isolated from CSF after inoculation in Castañeda medium.

[Predictive factors of acquisition of epidemic extended-spectrum beta-lactamase-producing Escherichia coli]. / Etude des facteurs prédictifs d'acquisition d'une souche épidémique d'Escherichia coli productrice de bêta-lactamase à spectre étendu.

The aim of the study was to determine predictive factors of epidemic extended spectrum beta-lactamase-producing Escherichia coli acquisition. All patients presenting any type of culture positive for ESBL-producing E. coli between November 2006 and October 2007 were included. An epidemic case was defined as a patient colonized with a clonal strain having epidemiological link with an another patient harbouring the same strain. Clinical and administrative data were recorded. Groups were compared by univariate and multivariate analysis using SAS software. Were included in this study 148 patients: 60 epidemic and 88 sporadic cases. Multivariate analysis showed several predictive factors of epidemic strain acquisition: female gender, high Charlson index, treatment by amoxicillin or ticarcillin-clavulanic acid, admission to emergency unit and hospitalisation in a high number of different care units. Identification of predictive factors of epidemic ESBL-producing E. coli strains acquisition may help to limit cross transmission of such strains.

[Real-time PCR for fast detection of plasmid-mediated qnr genes in extended spectrum beta-lactamase producing Enterobacteriaceae]. / Mise au point d'une technique de PCR en temps réel pour la détection rapide des gènes qnr chez des entérobactéries productrices de bêta-lactamases à spectre étendu.

AIM OF THE STUDY: To develop a fast and reliable real time PCR technique for detecting plasmid-mediated quinolone resistance genes qnrA, qnrB and qnrS. METHODS: A real-time PCR assay using SYBR Green I and Roche LightCycler(®) was developed to detect qnr genes. Detection of qnr genes was based on comparison of melting temperature differences with a positive control of each qnr genes. This assay was performed to study 138 isolates collected from diagnostic and screening samples in the Champagne-Ardenne region in 2004 (France). RESULTS: In optimized conditions, the three positive controls tested alone and with isolates confirmed the specificity of the PCR primers. Each PCR assay was able to test 30 strains in 60min for 1 qnr gene. Out of 138 isolates screened, 3.6 % isolates were positive for a qnrA1, 1.5 % for qnrS1 and no qnrB-like gene. Prevalence of qnr determinants was 5 % and reached 9.5 % in clinical isolates. CONCLUSION: Real-time PCR is a fast and reliable technique for screening of qnr-positive strains. This study shows a relatively high prevalence of qnr determinants (5 %) among ESBL-producing Enterobacteriaceae.

[Nocardia brain abscess: features, therapeutic strategies and outcome]. / Abcès cérébraux àNocardia: caractéristiques radiocliniques et prise en charge thérapeutique.

BACKGROUND AND PURPOSE: Nocardia species is an aerobic soil-saprophyte bacterium, responsible for rare opportunistic infections, mainly reported in immunocompromised patients. Nocardia brain abscess accounts for 1 to 2% of cerebral abscesses. Prognosis is poor. METHODS: We describe clinical, radiological and bacteriological findings along with therapeutic aspects for five patients and review the literature on Nocardia cerebral abscess. RESULTS: The clinical features of Nocardia brain abscess are insidious and nonspecific, occurring frequently with a medical background of obvious or latent immunodeficiency; fever, if any, is observed subordinate to extracerebral nocardiosis. Computerized tomography scan and conventional magnetic resonance (MR) scan show lesions with a necrotic core and multilobed thick walls enhancing after injection of gadolinium or iodine. Abscesses are mainly located in the brain stem, basal ganglia and cerebral cortex of the frontal, parietal and occipital lobes; cerebellar and spinal locations are uncommon. MR diffusion-weighted imaging with calculation of apparent diffusion coefficient and proton MR spectroscopy can provide additional data for accurate differential diagnosis between abscess and other necrotic lesions, such as tumor and cyst formations. Bacteriological identification has progressed with advances in molecular microbiology: 16S rRNA sequencing, allowing a more rapid routine identification of Nocardia strains from clinical samples. Clinical management of patients with a Nocardia brain abscess relies upon early use of intravenous antibiotics adapted to the strains identified and their susceptibility. Most Nocardia strains display susceptibility to cotrimoxazol, amikacin and linezolid, but develop beta-lactamase activity. CONCLUSIONS: Early pus samples, obtained by biopsy or surgical resection, are needed to establish a certain bacteriological diagnosis and initiate appropriate intravenous antibiotics.

[Bacillary endophthalmitis. Four case reports]. / Endophtalmie à bacillus. A propos de 4 cas.

PURPOSE: Bacillary endophthalmitis occurring after penetrating ocular trauma with an intraocular foreign body is always associated with poor visual outcome. Bacilli cause fulminant infection associated with tissue damage in the intraocular structures. CASE REPORTS: Our series consisted of four patients with penetrating ocular trauma and endophthalmitis caused by B. cereus or B. licheniformis. Three eyes ultimately developed phtisis. Only on eye recovered good vision (2.5/10 P4). DISCUSSION: Recommended early treatment includes topical, subconjunctival, parenteral antibiotics. A review of the literature indicates that intravitreal antibiotic infusion is crucial for sufficient concentration to control infection. Early vitrectomy is recommended in the management of endophthalmitis. Vitreous and intraocular foreign bodies should be cultured to identify pathogens and ascertain antibiotic susceptibilities.

[Current role of coagulase-negative staphylococci in urology]. / Place actuelle des staphylocoques à coagulase négative en urologie.

Coagulase-negative Staphylococci (CNS), considered for many years to be commensal bacteria of the skin are now recognized as major agents of nosocomial infection. Bacterial factors (increased resistance), host factors (immune status) and multiplication of the portals of entry (presence of foreign material) have contributed to the increased incidence of nosocomial infections. The importance of the role of NCS in urology is due to their great capacity to colonize catheters and most prostheses. The particular organization of these bacteria into a conglomerate called biofilm is responsible for prosthetic infections, which can impair renal function and can sometimes be life-threatening. The authors review the current increase of the number of CNS isolated in urology departments and describe the various therapeutic strategies that can be proposed to eradicate these bacteria.

Gastroscopy-associated transmission of extended-spectrum beta-lactamase-producing Pseudomonas aeruginosa.

An unusual multi-drug-resistant Pseudomonas aeruginosa (MDR-PA) was isolated in four patients whilst hospitalized in a French teaching hospital between May and August 2011. All four patients had undergone an oesophago-gastro-duodenoscopy with the same gastroscope over a five-month period. This endoscope was associated with a culture positive for the MDR-PA. Observations of endoscope reprocessing identified deviations from the agreed processes: insufficient initial cleaning, shortening of the immersion time and brushing time, insufficient channel flushing, and inadequate drying prior to storage. Since withdrawing the gastroscope and institution of strict adherence to the agreed processes, no other MDR-PA cases have been isolated.

Leptospira exposure in the human environment in France: A survey in feral rodents and in fresh water.

This paper confirms the important role of rodents to be maintenance hosts of leptospires. Their role is related to renal carriage and shedding of leptospires into urine, thus contaminating fresh water. Serological and carriage of feral rodents trapped in France were determined by MAT and hap1PCR specific for pathogenic leptospires. In same areas, fresh water samples were analyzed by hap1PCR. The overall seroprevalence was 44% in 649 rodents and was similar regardless of the species. Seroprevalence for leptospirosis is about 20-53% according to species. hap1PCR (516 kidneys) showed that renal carriage was higher in brown rats (34.7%) and muskrats (15.8%) than in coypus (3.3%). hap1PCR demonstrates a significative difference (P-value > 10(-12)) for the renal carriage between the different species: muskrats and rats are more efficient maintenance hosts than coypu but all infect water. Moreover 5/38 water samples associated with human cases were hap1PCR positive and 1/113 in controlled waters.

Incidence of class A extended-spectrum beta-lactamases in Champagne-Ardenne (France): a 1 year prospective study.

OBJECTIVES: To assess the frequency and diversity of extended spectrum beta-lactamases (ESBLs) in the Champagne-Ardenne region France, and to identify genetic elements associated with the bla(CTX-M) genes. METHODS: During 2004, all the non-duplicate isolates of Pseudomonas aeruginosa and Acinetobacter baumannii resistant to ceftazidime and of Enterobacteriaceae intermediate or resistant to ceftazidime and/or cefotaxime, screening samples excluded, were collected in 10 public hospitals and 3 private clinics. bla genes were sequenced and bla(CTX-M) environment characterized by PCR mapping. RESULTS: In Enterobacteriaceae (138/21 861; 0.6%), ESBLs were predominantly TEM-24 (n = 52; 37.7%) and CTX-M-15 (n = 37; 26.8%). Three new enzymes were identified, CTX-M-61 (CTX-M-1 group), TEM- and SHV-type. A. baumannii (n = 5) produced VEB-1 and P. aeruginosa (n = 2) SHV-2a. ISEcp1 was detected in 22/27 strains, disrupted in 7 of them. The IS903-like element was downstream of bla(CTX-M-14) and bla(CTX-M-16). ISCR1 was found upstream of bla(CTX-M-2) and bla(CTX-M-9), and ISCR1 and bla(CTX-M-2) were located on a sul1-type class 1 integron. In comparison with 2001-02, ESBL distribution among Enterobacteriaceae showed an increase in CTX-M-type (44.9% vs 3.7% P < 10(-7)) due to Escherichia coli CTX-M-15 and to the almost total disappearance of TEM-3 (0.9% vs 51.2%). E. coli was the most frequent species (50.0% vs 5.1% in 1998) despite a similar prevalence to that in 1998 (0.5% vs 0.2%). CONCLUSIONS: A careful detection of bla(CTX-M)-type spread to other species would help to anticipate clonal endemics such as those observed in Enterobacter aerogenes TEM-24.

Nocardia ignorata, a new agent of human nocardiosis isolated from respiratory specimens in Europe and soil samples from Kuwait.

Nocardia ignorata is a recently described species identified on the basis of a single isolate of unknown origin. Here we describe the epidemiological, phenotypic, and phylogenetic characteristics of this new species, based on five new clinical and soil isolates.

Isolation of an unusual Mycobacterium species from an AIDS patient with acute lymphadenitis.

A nonchromogenic Mycobacterium species was isolated from an AIDS patient with acute lymphadenitis. On the basis of the results of conventional tests, the strain appeared to be an atypical nonphotochromogenic Mycobacterium kansasii strain. Sequencing of the 16S rRNA gene revealed a unique nucleic acid sequence, suggesting that the isolate represents an undescribed pathogenic species.